Loom dobbies



T. HINDLE LOOM DOBBIES Sept. 22, 1970 3 Sheets-Sheet 1 Filed Sept. 13,1968 v INVENTOR: fiomayliz'zzdle BY 'i? q .31. t

T. HINDLE LQOM DOBBIES Sept. 22, 1970 3 Sheets- Sheet 2 Filed Sept. 13,1968 T. HlNDLE LOOM DOBBIES Sept. '22, 1970 3 Sheets-Sheet 5 Filed Sept.13, 1968 United States Patent 3,529,636 LOOM DOBBIES Thomas Hindle,Blackburn, England, assignor to Hindle, Son & Company Limited,Blackburn, England Filed Sept. 13, 1968, Ser. No. 759,550 Claimspriority, application Great Britain, Oct. 3, 1967, 44,855/ 67 Int. Cl.D03d 1/12 US. Cl. 139-77 9 Claims ABSTRACT OF THE DISCLOSURE The leverof a vibrator lever assembly for a Knowlestype loom head motion or dobbyis provided with a disclike part upon which the vibrator wheel isrotatably mounted. A cover plate secures the wheel in position upon anaxle pin extending from the said part, the cover plate being offsetrelative to the axle pin and being of generally L-shape to permit of thefree movement of a crank pin extending outwardly from the surface of thevibrator wheel through the plane of the cover plate during repeatedoscillating movement of the vibrator wheel between predetermined limitsand a connector mounted on the crank pin for oscillation therewith.

This invention relates to positive open-shed gear-dobbies, also known asloom head-motions, of the Knowlesyp In the conventional Knowleshead-motion, the jacklevers are of the two-arm or bell-crank form, andas all the crankpins are fixed in the vibrator-wheels at a commonradius, or throw, a graded shed is obtainable only by attaching thestreamers at progressively greater radius along the two arms of thejack-levers, as viewed from front to back. The connectors, which linkthe said crankpins to the upstanding arms of the jack-levers, arenecessarily curved and also attenuated at their crankpin ends in orderto provide physical clearance, firstly, above the axle pin lug on thevibrator lever, and, secondly, below the teeth of the top drivingcylinder, and consequently the dimensions and strength of the connectorsthemselves, also the bearing area of the axle pins and crankpins, arerestricted in practice.

The principal object of the present invention is to provide an improvedconstruction for the unit assembly comprising the vibrator lever, thevibrator gear-wheel and the connector, whereby the axle pins andcrankpins may be made relatively large in diameter and bearing area or,alternatively and preferably, fitted with ball or roller bearings, whilethe connectors are straight instead of curved, and may be made of amplestrength, the said construction permitting, when so required, thecrankpin in each vibrator-wheel, as viewed from front to back, to befixed at a progressively greater radius instead of at a common radius.

According to the present invention a vibrator lever assembly for aKnowles type loom head motion or dobby comprises a vibrator lever,embodying a plate-like part, an axle pin carried by such part, avibrator wheel rotatably mounted on the axle pin, the said vibratorwheel having a crank-pin extending therefrom at that side thereof remotefrom the plate-like part, a cover plate secured to the said plate-likepart and extending across the face of the vibrator wheel over a part ofthe periphery thereof and in closely adjacent relation thereto thus tomaintain the vibrator wheel in position upon the axle pin, the saidcover plate being adapted and arranged to permit free to and fromovement of the crank pin and a connector supported thereon Within alimited range of movement during repeated oscillating motion of thevibrator wheel.

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Preferably the cover plate is generally L-shaped and is mounted upon thelever in off-set relationship to the axle pin.

By the adoption of the electrically-controlled fluidpressure relaymechanism described in co-pending US. Pat. No. 3,460,582, for thepurpose of setting and retaining the vibrator levers and theirgear-wheels in their operative positions, these components are renderedindependent of gravity for their operation, thereby enabling the entirelayout of the conventional Knowles head motion to be rearranged tobetter advantage from the particular viewpoint of heavy duty.

The invention will now be described further, by way of example only,with reference to the accompanying drawings in which:

FIG. 1 is an elevation, omitting the frame, of the improved head-motion,or dobby, as adapted to actuate horizontal jack-levers;

FIG. 2 is an edge-view of two adjacent improved unit assemblies;

FIG. 3 is a front elevation, drawn to larger scale, of the improved unitassembly;

FIG. 3A shows the general banjo form of the vibratorlever;

FIG. 3B shows the vibrator-wheel;

FIG. 3C shows the cover plate; and

FIG. 3D shows a modification of the connector.

Referring to FIG. 1, the horizontal jack-levers 1 swing on their commonfulcrum bar 2, and operate the head shafts (not shown) through verticaltension members T and B, end pulleys P, horizontal streamers S, andother pulleys and tie-ups (not shown). The said tension members T and Bare attached to the jack-levers 1 at a common radius from their fulcrum2 by the swivels 3a. Each jack-lever, by hinge-pin 3 located aboutmidway in its length, is linked by straight connector 4 to the overhungcrankpin 4a, fixed at a suitable radius in each vibrator- Wheel 5, whichwheel rotates on the overhung axle-pin 5a fixed in the disc 6d (FIG. 3A)at the top of the vertical vibrator lever 6, which lever swings on thecommon fulcrum bar 7. These fulcrum bars 2 and 7, as also the throughbars 12 and 32, are supported by the frames (not shown).

The vibrator-wheels S are adapted in the usual manner to be rotated ahalf-turn at a time, first in one direction and subsequently in theother, by their meshing alternately with the partly-toothed drivingcylinders 8 and 9, such cylinders rotating continuously in oppositedirections, as indicated by the arrows. Each vibrator lever 6 swingsover sufiiciently to set its vibrator-wheel 5 in meshing distance witheither the lift cylinder 8 or the lowering cylinder 9. These settingoperations are preferably performed by the electrically-controlledfluid-pressure means described in our aforesaid co-pending US. Pat. No.3,460,582, one form of such means comprising a double-acting slavecylinder 11 which is flexibly anchored to the through-bar 12, while itspiston-rod 11a is hinged at 6a to the upper end of the vibrator lever 6.The action of each slave cylinder is governed by an electromagneticallyactuated valve 13 under the control of a pattern switch 16 in accordancewith the indications of a pattern chain 18 or the like.

According to the first part of the invention, as shown by theaccompanying drawings, the upper end of each vibrator lever 6 takes thegeneral form of a circular plate or disc 6d in the centre of which isfixed the overhung axle-pin 5a, on which the vibrator-wheel 5 rotates.An overhung crankpin 4a is similarly fixed at a suitable radius in eachvibrator-wheel. The entire rear rim of the wheel 5 is in free contactwith the front face of the disc 6d, FIG. 2, and the wheel is retained inthat location on its axle-pin a by a cover plate 31, which spans andpartly encloses the wheel 5, and is secured by screws 6m to the disc 6d.This cover plate 31 thus occupies the same plane as the connector 4, andwhile it aflFords lateral location and support for the vibrator-wheel,it is so shaped as to clear the semi-circular path of the crankpin 4aand the straight connector 4, and also to allow the vibrator-wheel tomesh with either cylinder as and when required.

The cover plate 31 is of generally L-shaped and its outline or shape isbest shown in FIG. 3C. The lower arcuate profile encloses, over a wideangle, the front rim of the wheel 5, thereby ensuring its lateralstability under the forces sustained by the overhung crankpin 4a. It ispreferred that the external circular profile 6s of the cover plate bemade to register into a corresponding circular recess machined in thedisc at 61, as shown in FIGS. 2, 3 and 3A.

Each vibrator-wheel 5 may be provided, in the usual manner, with asemi-circular slot or groove 5p (FIG. 3B), the extreme ends of whichengage a stop-pin 60 (FIGS. 3, 3A) to limit the rotation. Alternatively,as shown in FIG. 3D, and with the same effect, the boss at the crankpinend of the straight connector 4 may be provided with a pad 40, adaptedto abut against the co-planar cover plate 31.

The extreme top end of each vibrator lever 6 is provided with a machinegroove 35, FIG. 3A, adapted to be engaged and guided by one of a seriesof pegs or rollers such as 33 (FIG. 3), projecting downwards from athrough-bar 32, thereby ensuring accurate spacing and alignment of thevibrator levers during their swinging movement, and under the heaviestshedding loads. The upper end of each vibrator lever is also providedwith a lug for the hinged attachment by pin 6a of the pistonrod 11a ofthe slave cylinder 11, or, alternatively, of an intermediatetoggle-linkage actuated by that cylinder, in the general manner and forthe purpose described in the above-mentioned co-pending U.S. Pat. No.3,460,582.

Horizontal, single-armed jack-levers are preferred for heavy work asbeing more compact and inherently stronger than the customary bell-cranklevers, and they are also more conveniently and tidily connected to theheald shafts, as will be apparent from FIG. 1. The vertical connectionsT and B, are linked to the jack-levers 1 at a common radius r, and thegraded shed is provided in the preferred manner by fixing the crankpinsin the vibrator-wheels, as viewed from front to back, at a progressivelygreater radius, which graduation is facilitated by the constructionherein described.

The crank radius arm of the vibrator-wheel 5 and the connector 4 arearranged in the usual manner to form a toggle-lock at each end of thesemi-rotary movement of the wheel, so as to sustain the heald shafts intheir openshed positions whenever the gears are not in mesh.

It is preferred to divide the improved head-motion into two parts, onesuch part being located at each end of the loom, but with both suchparts controlled by a singlepattern-barrel located in any convenientposition, usually at one end of the loom, in the manner of theabove-mentioned co-pending application. The arrangement is such that theodd-numbered heald shafts are actuated by one part, and the evennumbered from the other part of the head-motion, or dobby, whereby, inthe usual manner the shaft-actuating components, viz: the vibratorlever, its wheel and connector, may have a combined thickness equal totwice the pitch of the heald shafts.

The horizontal jack-lever 1 shown in FIG. 1, may be provided withadditional means, as described in our copending U.S. application Ser.No. 759,653, enabling any heald shaft to be slightly raised or loweredby a single adjustment accessible at the end of the loom, therebyobviating the laborious operation of adjusting all the top and bottomtie-ups appertaining to each shaft in a wide loom.

Springs may be fitted to ensure completion of the vibrator-wheelshalf-turns, for example, a tension spring may be hinged to the connectorabout midway in its length and the other end anchored either to astationary through-bar or to the co-acting jack-lever adjacent to thefulcrum. Alternatively, compression springs may be applied withequivalent effect.

The improved head-motion or dobby mechanism may be adapted for actuatingdrop-boxes and/or for controlling pick-at-will picking motions.

What I claim is:

1. A vibrator lever assembly for a loom head motion comprising avibrator lever, embodying a plate-like part, an axle pin carried by saidplate-like part, said axle pin extending from the plate-like part withits axis substantially perpendicular thereto, a vibrator wheel rotatablymounted on said axle pin close to and substantially parallel to saidplate-like part, a crank pin carried by said vibrator wheel, said crankpin extending from the vibrator wheel at the side remote from theplate-like part and substantially perpendicular thereto, a connectorrotatably supported by said crank pin close to and substantiallyparallel to said vibrator wheel at the side remote from the plate-likepart and a cover plate secured to said plate-like part close to andparallel to the face of the vibrator wheel, said cover plate covering apart of the periphery of the vibrator Wheel thus to maintain thevibrator wheel in position on said axle pin, said cover plate beingadapted and arranged to permit free to-and-fro movement of the crank pinand the connector supported thereon within a limited range of movementduring repeated oscillating movement of the vibrator wheel.

2. A vibrator wheel assembly as claimed in claim 1, wherein thecover-plate is generally L-shaped and is mounted upon the plate-likepart in off-set relationship to the axle pin.

3. A vibrator lever assembly according to claim 1, wherein saidplate-like part has at the side from which the axle pin extendslaterally extending portions at each of two spaced locations, and saidcover plate extends between and is secured to said portions.

4. A vibrator lever assembly according to claim 3, wherein said portionsare each recessed to receive the cover plate into registrationtherewith.

5. A vibrator lever assembly according to claim 3, wherein saidplate-like part has a groove in an edge there of, disposed at rightangles to the axis of the vibrator wheel adapted to receive a fixedguide into engagement therewith.

6. A vibrator lever assembly according to claim 1 including stop meansadapted to limit the extent of rotation of the vibrator wheel relativeto the lever.

7. A vibrator lever assembly according to claim 6 wherein an edge of thecover plate constitutes the said stop means.

8. A vibrator lever assembly according to claim 7, wherein saidconnector includes a pad operable by contact with said edge of the coverplate to limit the extent of movement of the vibrator wheel relative tothe lever.

9. A vibrator lever assembly according to claim 1 wherein the saidconnector is straight.

References Cited UNITED STATES PATENTS 490,106 1/1893 Falvey 139-77860,715 7/1907 Wattie 13977 1,053,307 2/1913 Livermore 139-77 1,112,87410/1914 Wattie 13977 1,451,797 4/1923 Wattie 13977 JAMES KEE CHI,Primary Examiner

